#include <iostream>
#include <GL/glew.h>
#include <GL/freeglut.h>
#include <GL/glext.h>

#include <cmath>

using namespace std;

GLfloat Eye_X, Eye_Y, Eye_Z;

int Draw_State;

void DisplayString(void * font, string s) {
    int i;

    for(i=0; i < s.size(); i++) {
        glutStrokeCharacter(font, s[i]);
    }

    return;
}

void Cube() {
    glBegin(GL_QUADS);
       // front face
       glVertex3f(-0.5, -0.5, -0.5);
       glVertex3f(0.5, -0.5, -0.5);
       glVertex3f(0.5, 0.5, -0.5);
       glVertex3f(-0.5, 0.5, -0.5);
       // Back face
       glVertex3f(-0.5, -0.5, 0.5);
       glVertex3f(0.5, -0.5, 0.5);
       glVertex3f(0.5, 0.5, 0.5);
       glVertex3f(-0.5, 0.5, 0.5);
       // left face
       glVertex3f(-0.5, -0.5, -0.5);
       glVertex3f(-0.5, -0.5, 0.5);
       glVertex3f(-0.5,  0.5, 0.5);
       glVertex3f(-0.5,  0.5, -0.5);
       // right face
       glVertex3f(0.5, -0.5, -0.5);
       glVertex3f(0.5, -0.5, 0.5);
       glVertex3f(0.5,  0.5, 0.5);
       glVertex3f(0.5,  0.5, -0.5);
       // top face
       glVertex3f(-0.5, 0.5, -0.5);
       glVertex3f(0.5,  0.5, -0.5);
       glVertex3f(0.5,  0.5, 0.5);
       glVertex3f(-0.5, 0.5, 0.5);
       // bottom face
       glVertex3f(-0.5, -0.5, -0.5);
       glVertex3f(0.5,  -0.5, -0.5);
       glVertex3f(0.5,  -0.5, 0.5);
       glVertex3f(-0.5, -0.5, 0.5);

    glEnd();
}

void DrawChar(void * font, char c, GLfloat xs, GLfloat ys, GLfloat zs,
             GLfloat xr, GLfloat yr, GLfloat zr) {
     GLfloat width,
             height,
	     big,
	     scale;


     
     width =  glutStrokeWidth(font,c);
     big = width;
     height = glutStrokeHeight(font);
     if (height > big) {
        big = height;
     }

     scale =  0.7 / big;

     glPushMatrix();
     glTranslatef(xs,ys,zs);
     glRotatef(xr, 1, 0, 0);
     glRotatef(yr, 0, 1, 0);
     glRotatef(zr, 0, 0, 1);
     glScalef(scale, scale, scale);
     glTranslatef(-width/2.0,-height/2.0,0);
     glutStrokeCharacter(font, c);
     glPopMatrix();

     return;
}


void Die() {
    void * fontID = GLUT_STROKE_ROMAN;


    Cube();

    if (Draw_State > 1) {
        // draw the numbers: 
        DrawChar(GLUT_STROKE_ROMAN,'1',  0.0, 0.0, 0.5, 0, 0, 0);
        DrawChar(GLUT_STROKE_ROMAN,'2',  0.5, 0.0, 0.0, 0, 90, 0);
        DrawChar(GLUT_STROKE_ROMAN,'3',  0.0, 0.5, 0.0,-90, 0, 0);
        DrawChar(GLUT_STROKE_ROMAN,'4',  0.0,-0.5, 0.0, 90, 0, 0);
        DrawChar(GLUT_STROKE_ROMAN,'5', -0.5, 0.0, 0.0, 0, -90, 0);
        DrawChar(GLUT_STROKE_ROMAN,'6',  0.0, 0.0, -0.5, 0, 180, 0);
    }


}

void Axis() {
   glColor3f(0,0,0) ;

   glBegin(GL_LINES) ;
      glVertex3f(0,0,0);
      glVertex3f(1,0,0);
      glVertex3f(0,0,0);
      glVertex3f(0,1,0);
      glVertex3f(0,0,0);
      glVertex3f(0,0,1);
   glEnd();

   DrawChar(GLUT_STROKE_ROMAN, 'x',1,0,0, 0,0,0);
   DrawChar(GLUT_STROKE_ROMAN, 'y',-0.25,1,0, 0,0,0);
   DrawChar(GLUT_STROKE_ROMAN, 'z',0,0,1, 0,0,0);

   return;
}


void display() {
   glClear(GL_COLOR_BUFFER_BIT);
   glLoadIdentity();

   if (Draw_State > 4) {
       gluLookAt(Eye_X,Eye_Y,Eye_Z, 2.5, 1.0 , -3.5, 0, 1, 0);
   } else {
       gluLookAt(Eye_X,Eye_Y,Eye_Z,0,0,0,0,1,0);
   }

   if (Draw_State < 5) {
       Axis();
   }

   glColor3f(1,0,0);

   if (Draw_State > 0) {

       if (Draw_State > 2) {
          glPushMatrix();
	  if (Draw_State > 3) {
	     glTranslatef(3, 0.5, -4);
	  }
	  glRotatef(-90,1,0,0);
       }
       Die();
       if (Draw_State > 2) {
	  glPopMatrix();
       }
   }

   glColor3f(0,1,1);
   if (Draw_State > 4) {
       glPushMatrix();
       glTranslatef(2, 0.5, -3);
       glRotatef(180,0,0,1);
       glRotatef(45,0,1,0);
       Die();
       glPopMatrix();
   }

   glFlush();
   return;
}

void reset() {
   Eye_X = 0;
   Eye_Y = 0;
   Eye_Z = 2.2;

   Draw_State = 0;

   return;
}

void setup() {
   reset();
   glPolygonMode(GL_FRONT_AND_BACK, GL_LINE);
   glClearColor(1,1,1,0);

   return;
}

void resize(int w, int h) {
   glViewport(0, 0, w, h);
   glMatrixMode(GL_PROJECTION);
   glLoadIdentity();
   glFrustum(-1.5,1.5,-1.5,1.5,1,10);
   glMatrixMode(GL_MODELVIEW);
   glLoadIdentity();

   return;
}


void  keypress (unsigned char key, int x, int y) {

   GLfloat cameraMove = 0.25;

   switch(key) {
     case '+':
        Draw_State ++;
	break;
     case '-':
        Draw_State--;
	break;
     case '8':
        Eye_Y += cameraMove;
	break;
     case '2':
        Eye_Y -= cameraMove;
	break;
     case '6':
        Eye_X += cameraMove;
	break;
     case '4':
        Eye_X -= cameraMove;
	break;
     case '1':
        Eye_Z += cameraMove;
	break;
     case '3':
        Eye_Z -= cameraMove;
	break;
     case 'r':
        reset();
	break;
     case 'q':
          exit(0);
   }
   glutPostRedisplay();
   return;
}

int main(int argc, char * argv[]) {
   
   reset();
   glutInit(&argc, argv);

   glutInitContextVersion(3, 0);
   glutInitContextProfile(GLUT_COMPATIBILITY_PROFILE);

   glutInitDisplayMode(GLUT_SINGLE | GLUT_RGBA);
   glutInitWindowSize(500, 500);
   glutCreateWindow("A Demo");
   glutDisplayFunc(display);
   glutReshapeFunc(resize);
   glutKeyboardFunc(keypress);

   glewExperimental = GL_TRUE;
   glewInit();

   setup();

   glutMainLoop();
}